NO, that's weird. Even though the tube looks like it matches if they were both placed in the same glass. They should not send a pair to you like that. Send it back, get two new identical ones. That's not cool.
my amp tech actually put them in for me while he was doing some other work a couple weeks ago. i didn't order them. He is a reputable tech here and has never steered me wrong.
Having said that, the amp just died on me and blew the HT fuse. This is the same problem I took it in for last time. I'm not sure what to think about it. I wonder if its those tubes. I just now noticed the sizes were different.